As stated, where to where is key. I have heard everything from $600 and up coast to coast in the States. For reference, the company we used to bring one of the cars over here was $2100 and that was not in a separate container, but was darn near door to door. Car was filthy, but generally unharmed. I've heard horror stories.
Honestly, I think it is a crap shoot. Just make sure you have insurance of some sort.